A display interface may be disposed between an application processor (AP) and a display driver integrated circuit (DDIC) to transmit display data from the AP to the DDIC for further processing. When a display panel supports a higher display resolution, 2D/3D display with higher resolution can be realized. Hence, the display data transmitted over the display interface would have a larger data size/data rate, which increases the power consumption of the display interface inevitably. If the AP and the DDIC are both located at a portable device (e.g., a smartphone) powered by a battery device, the battery life is shortened due to the increased power consumption of the display interface.
Similarly, a camera interface may be disposed between a camera module and an image signal processor (ISP) to transmit multimedia data from the camera module to the ISP for further processing. The ISP may be part of an application processor. When a camera sensor with a higher resolution is employed in the camera module, the captured image data transmitted over the camera interface would have a larger data size/data rate, which increases the power consumption of the camera interface inevitably. If the camera module and the ISP are both located at a portable device (e.g., a smartphone) powered by a battery device, the battery life is shortened due to the increased power consumption of the camera interface.
Data compression may be employed to reduce the data size/data rate of picture data transmitted over a transmission interface such as the display interface or the camera interface. To enable parallel processing in an encoder side, a decoder side, or both, partitioning one picture into multiple picture regions (e.g., slices or tiles/panes) is proposed. However, concerning a single-port compressed data transmission application, it is possible that a slice width is not evenly divisible by a pixel group width. Similarly, concerning a multi-port compressed data transmission application, it is possible that a tile/pane width is not evenly divisible by a pixel group width. A typical encoder design may employ pixel padding to obtain needed pixels. For example, one existing pixel may be replicated to create one or more padding pixels. However, the slice boundary condition may make the processing more complicated, and such a pixel padding operation does not consider the visual quality. Further, adjacent picture regions are encoded independently. The visual quality of a boundary between the adjacent picture regions may be degraded due to significant discrepancy between quantization parameters assigned to pixel groups on opposite sides of the boundary.